Reef Tank Crash

ScolyThor · Sep 30, 2023

Hi all,

I could use some help with a tank issue i'm currently dealing with.

Summer temperatures here get quite hot, and so I had turned down my heater. I had noticed tank temperatures were somewhat low (76.5 F or so), but nothing crazy. I recently upgraded to a Reefer 350, and kept the old 200W heater (slightly undersized).

Well, temperatures dipped down to about 75F for a few days. I discovered they had been low when I returned from a 30 hour shift in the hospital, and quickly took corrective action.

I upgraded my heater, obtained an ink bird, and have targeted a range of 77-78. Temps have been stable since.

Despite the corrective action, I have continued to observe bleaching in my setosa, and now my hammer (large colony of 40+ heads) is melting back at the bases with poor polyp extension. I have performed one water change, and been target feeding benereef to every coral daily to try and assist them through this. I plan to perform another water change in the morning.

I performed a water change, put in new carbon, have been skimming aggressively, and changing filter socks every other day.

Parameters are as follows:
Temp 77.3
Salinity 1.025
pH 8.15 (8-8.3 diurnal)
NO3: 0 (I dose Fuel daily)
PO4: 0 (also dose fuel daily)
KH: 8.6
Ca: 440
Mg: 1350

I am now 6-7 days out from the event, and feel like things have steadily been declining despite all my best efforts. I'm unsure if this is just expected after letting the temps get too low, or if there is some parameter i'm not measuring that could be contributing.

Tank details: mixed reef Reefer 350.
Corals: orange setosa montipora, large hammer colony, zoas all over the place, Warpaint scoly, gold torch coral, orange plate coral, mushrooms all over, some gonipora.

Thanks for your help everyone

Dan_P · Sep 30, 2023

ScolyThor said:
Hi all,

I could use some help with a tank issue i'm currently dealing with.

Summer temperatures here get quite hot, and so I had turned down my heater. I had noticed tank temperatures were somewhat low (76.5 F or so), but nothing crazy. I recently upgraded to a Reefer 350, and kept the old 200W heater (slightly undersized).

Well, temperatures dipped down to about 75F for a few days. I discovered they had been low when I returned from a 30 hour shift in the hospital, and quickly took corrective action.

I upgraded my heater, obtained an ink bird, and have targeted a range of 77-78. Temps have been stable since.

Despite the corrective action, I have continued to observe bleaching in my setosa, and now my hammer (large colony of 40+ heads) is melting back at the bases with poor polyp extension. I have performed one water change, and been target feeding benereef to every coral daily to try and assist them through this. I plan to perform another water change in the morning.

I performed a water change, put in new carbon, have been skimming aggressively, and changing filter socks every other day.

Parameters are as follows:
Temp 77.3
Salinity 1.025
pH 8.15 (8-8.3 diurnal)
NO3: 0 (I dose Fuel daily)
PO4: 0 (also dose fuel daily)
KH: 8.6
Ca: 440
Mg: 1350

I am now 6-7 days out from the event, and feel like things have steadily been declining despite all my best efforts. I'm unsure if this is just expected after letting the temps get too low, or if there is some parameter i'm not measuring that could be contributing.

Tank details: mixed reef Reefer 350.
Corals: orange setosa montipora, large hammer colony, zoas all over the place, Warpaint scoly, gold torch coral, orange plate coral, mushrooms all over, some gonipora.

Thanks for your help everyone

A dip in temperature to 75 F does not seem a likely cause. If coral were that sensitive to temperature changes, shipping coral would be impossible.

How old is the system?

Mr. Mojo Rising · Sep 30, 2023

I would think the zero nitrates and zero phosphates will have more to do with your troubles than a 2 degree temp change. Pics usually help a lot to give us visual idea.

ScolyThor · Sep 30, 2023

Dan_P said:
A dip in temperature to 75 F does not seem a likely cause. If coral were that sensitive to temperature changes, shipping coral would be impossible.

How old is the system?

The system was established 6 weeks ago, but was setup from a 60 gallon cube, with all the same live rock. I added a bit more live sand, and one new dry rock to the tank a few weeks ago.

ScolyThor · Sep 30, 2023

Mr. Mojo Rising said:
I would think the zero nitrates and zero phosphates will have more to do with your troubles than a 2 degree temp change. Pics usually help a lot to give us visual idea.

I can increase dosing for sure. But my system has been stable with these nitrates and phosphates for quite a long time. I dose Fuel (aminos and vitamins) and feed very heavily (frozen 2x daily, plus algae pellets once a day and a sheet of nori once a day, as well as benereef twice a week)

brandon429 · Sep 30, 2023

the abosolute #1 step you take is to remove the white spectrum from any tubable lighting, and drop overall power down - 40-50% and sustain that a good while in slow ramp up

any day your corals are getting full adapted power lighting is a day of sunburn for them after insults...alk insults also included along with temp ones.

lighting control only would have prevented this. my coldest heater outage insult was 68 degrees not caught for 4 months. I couldn't figure out what was causing my bleaching but I did keep lowering the lighting with each passing week it got worse, that stopped a total wipeout.

then when found the heater was simply blown out/68 degrees during most of the winter 2020, I fixed the heating and slowly ramped up over two months with strong feed and water changes. that's the order of cpr for stress induced bleaching, it's by light modulation

ScolyThor · Sep 30, 2023

Mr. Mojo Rising said:
I would think the zero nitrates and zero phosphates will have more to do with your troubles than a 2 degree temp change. Pics usually help a lot to give us visual idea.

ScolyThor · Sep 30, 2023

brandon429 said:
the abosolute #1 step you take is to remove the white spectrum from any tubable lighting, and drop overall power down - 40-50% and sustain that a good while in slow ramp up

any day your corals are getting full adapted power lighting is a day of sunburn for them after insults...alk insults also included along with temp ones.

lighting control only would have prevented this. my coldest heater outage insult was 68 degrees not caught for 4 months. I couldn't figure out what was causing my bleaching but I did keep lowering the lighting with each passing week it got worse, that stopped a total wipeout.

then when found the heater was simply blown out/68 degrees during most of the winter 2020, I fixed the heating and slowly ramped up over two months with strong feed and water changes. that's the order of cpr for stress induced bleaching, it's by light modulation

That's good to know. I haven't decreased my lighting yet, and will do so promptly. Thanks!

ScolyThor · Oct 5, 2023

Just wanted to close the loop on this one.

I turned off all white lights, and did a 30 day acclimation setting on my lights with initial decrease to 30% of blues. After ramping up the blues over 30 days I will slowly add back whites over the following month.

Things continued to get worse after the above photos, but have subsequently plateaued and started to bounce back.

Pretty sure I will lose my Scolymia coral pictured above. The orange setosa got worse, but is now bouncing back. Hammer coral has stabilized and is working its way back.

Every other coral (zoas, mushrooms, etc) is looking much better, with the exception of my gold goniopora corals. They haven't died, but haven't recovered much either. I'm hoping to save them still.

Thanks everyone for the advice! In the future, at the first sign of coral stress I will drop the white lights and dim my blues to a slow acclimation, as this seems to be what turned the tides here.

Thanks!